The present invention relates to apparatus for transporting rod-shaped articles, especially rod-shaped articles (such as plain or filter cigarettes, cigars, cigarillos or filter rod sections) which constitute or form part of smokers' products. More particularly, the invention relates to improvements in apparatus for transporting rod-shaped articles by resort to a transporting unit which has at least one article diverting portion and at least one junction serving to receive articles from a source other than the main source of supply. Still more particularly, the invention relates to improvements in transporting apparatus of the type wherein the diverting portion of the just discussed (first) transporting unit is connected with the junction by a second transporting unit having a tray filler which receives articles from the diverting portion of the first transporting unit and a tray evacuator which receives filled trays from the tray filler and converts the contents of filled trays into a stream of rod-shaped articles which are admitted to the junction of the first transporting unit. In such apparatus, the second transporting unit normally further comprises a first conveying section which delivers filled trays from the tray filler to the tray evacuator and a second conveying section which serves to deliver the stream of articles from the tray evacuator to the junction.
Rod-shaped articles of the tobacco processing industry embrace a variety of articles which do not consist of mirror symmetrical halves. Typical examples of such articles are filter cigarettes, cigarillos or cigars wherein the filter is disposed at one end and the remaining portion of the article constitutes a wrapped tobacco filler. Furthermore, such articles also include plain cigarettes wherein the imprint (denoting the name and/or the trademark of the manufacturer) is disposed nearer to the one than to the other axial end thereof. Prior to introducing such "unsymmetrical" rod-shaped articles into packs, boxes or other types of receptacles in which the articles are offered for sale to smokers, it is necessary to ensure that the orientation of all articles is the same, e.g., that the filters of filter cigarettes, cigars or cigarillos face in the same direction. This is the customary way of introducing such articles into packs or the like. It can be readily ascertained that, on opening of a pack of filter cigarettes, the filter plugs of all cigarettes in the pack are adjacent to the open end so that the cigarettes can be removed individually or in groups by engaging their filter plugs rather than the tobacco-containing portions of such commodities.
Direct coupling of making and processing machines or first and second processing machines is gaining in popularity in a number of industries, especially in the tobacco industry. Thus, it is now quite customary to directly connect a cigarette maker with one inlet of a filter tipping machine, to directly couple another inlet of the filter tipping machine with the maker of filter rod sections, and to directly couple the outlet of the filter tipping machine with a packing machine so that the production line including such machines makes the plain cigarettes and the filter rod sections, assembles plain cigarettes and filter rod sections into filter cigarettes of unit length, and introduces filter cigarettes into packs which are sealed, provided with transparent wrappers of cellophane or the like, and introduced into cartons which are thereupon inserted into boxes or cartons ready for storage or for immediate shipment to wholesalers or retailers. The connections between the machines of a complete production line normally constitute transporting units which are capable of advancing multi-layer streams of rod-shaped articles in such a way that the articles advance in a direction at right angles to their axes (i.e., sideways). The main or first transporting unit between two successive machines is normally combined with a second or auxiliary transporting unit which constitutes a reservoir or magazine and takes care of fluctuations in the output of the preceding machine and of fluctuations in the requirements of the next-following machine. For example, the second transporting unit between a filter tipping machine and a packing machine can comprise a tray filler which accepts the surplus of the output of the filter tipping machine when such output exceeds the requirements of the packing machine. The second transporting unit further comprises a tray evacuator which receives filled trays from the tray filler and converts the contents of trays into a stream of articles which are returned to the first transporting unit when the output of the filter tipping machine does not match the requirements of the packing machine.
An apparatus of the just outlined character is disclosed, for example, in German Offenlegungsschrift No. 30 13 014. The tray filler is directly coupled with the tray evacuator by a conveying section wherein the filled trays advance into the range of the tray evacuator. This is desirable and advantageous because the diversion of surplus articles from the first transporting unit into the tray filler, the filling of empty trays, the transport of the thus obtained filled trays from the tray filler to the tray evacuator, and the conversion of the contents of filled trays into a stream of rod-shaped articles can be effected automatically. However, the last stage of the transport of temporary surplus back into the first transporting unit presents problems because, as a rule, a tray evacuator changes the orientation of articles which are removed from filled trays and converted into a stream of parallel articles which are ready to move sideways. In connection with the treatment of filter cigarettes, this means that the orientation of filter cigarettes which have been diverted from the first transporting unit (to be fed into trays, transported with trays and converted into a stream of articles) is changed by 180.degree. so that they cannot be automatically returned into the first transporting unit since the latter would then contain cigarettes having a first orientation (namely, the orientation imposed upon them by the filter tipping machine which discharges the articles into the first transporting unit) as well as cigarettes having a second orientation (namely, the orientation imposed by the tray evacuator). Therefore, the apparatus of the German publication is not suitable for fully automatic operation and has failed to gain widespread acceptance in the tobacco processing industry. If such apparatus is used between a filter tipping machine and a packing machine, filled trays are supplied to its tray evacuator by hand so that the articles which are evacuated from filled trays and converted into a multi-layer or single-layer stream have the same orientation as the articles in the first transporting unit, i.e., the stream which is formed by the tray evacuator, can be admitted directly into the first transporting unit for advancement into the packing machine with the articles which did not leave the first transporting unit on arrival at the diverting station. Such manual feeding of filled trays to the tray evacuator is a time-consuming and cumbersome procedure which necessitates constant attendance by one or more workmen and the establishment of an adequate supply of filled trays at a location not overly remote from the tray evacuator. In fact, when filled trays are to supplement the output of a filter tipping machine which normally turns out very large quantities of articles per unit of time, the speed of the packing machine must be reduced or the packing machine must be brought to a full stop whenever the output of the filter tipping machine decreases only slightly below the normal output. This entails very high losses in output, especially in a modern production line which can turn out in excess of 7000 cigarettes per minute.